Only 3 SF books in Amazon's top 25 SF&F best sellers

As of just now when I checked, there are only 3 Science Fiction books in Amazon.co.uk Hot 25 Science Fiction & Fantasy. Those books are Serenity, Star Wars Outbound Flight and Judas Unchained by Peter F. Hamilton. Surely that isn't a god omen for SF in the UK?

The US list fares a little better with 10 SF books in the top 25.